University of Jyväskylä

About: University of Jyväskylä is a education organization based out in Jyvaskyla, Finland. It is known for research contribution in the topics: Population & Context (language use). The organization has 8066 authors who have published 25168 publications receiving 725033 citations. The organization is also known as: Jyväskylän yliopisto & Kasvatusopillinen korkeakoulu.

Oral Hygiene Habits of 11-year-old Schoolchildren in 22 European Countries and Canada in 1993/1994

Abstract: This study is part of the Cross-National Survey on Health Behaviour in School-aged Children--a WHO Collaborative Study, which started in 1982. The aim of the study was to describe the oral hygiene habits (toothbrushing and flossing) of 11-year-old schoolchildren in 22 European countries (Austria, Belgium, the Czech Republic, Denmark, Estonia, FInland, France, Germany, Greenland, Hungary, Israel, Latvia, Lithuania, Northern Ireland, Norway, Poland, Russia, Scotland, the Slovak Republic, Spain, Sweden, and Wales) and Canada. The data were collected from standardized anonymous questionnaires in school classrooms during the 1993-1994 school year. At least 1300 school children, representing the whole country, participated in the study in each country. Oral hygiene habits were analyzed according to gender, age, country, school performance, and family economy. The children brushed most favorably in Sweden, Denmark, German, Austria, and Norway (83-73% brushed twice a day). More-than-once-a-day toothbrushing was especially uncommon (from 26 to 33%) among boys in Finland, Lithuania, Russia, Estonia, and Latvia. Toothbrushing frequency differed significantly according to school performance in Canada, the Czech Republic, Scotland, Poland, Northern Ireland, and Wales and between different socio-economic groups in Northern Ireland, Wales, the Czech Republic, Scotland, Poland, and Russia. Use of dental floss was rare. In general, flossing was less frequent among boys than among girls. Daily flossing was most common among Canadian adolescents (25%). In conclusion, there are considerable differences in toothbrushing frequency among children in European countries.

Result of the search for neutrinoless double-$\beta$ decay in $^{100}$Mo with the NEMO-3 experiment

Abstract: The NEMO-3 detector, which had been operating in the Modane Underground Laboratory from 2003 to 2010, was designed to search for neutrinoless double $\beta$ ($0 u\beta\beta$) decay. We report final results of a search for $0 u\beta\beta$ decays with $6.914$ kg of $^{100}$Mo using the entire NEMO-3 data set with a detector live time of $4.96$ yr, which corresponds to an exposure of 34.3 kg$\cdot$yr. We perform a detailed study of the expected background in the $0 u\beta\beta$ signal region and find no evidence of $0 u\beta\beta$ decays in the data. The level of observed background in the $0 u\beta\beta$ signal region $[2.8-3.2]$ MeV is $0.44 \pm 0.13$ counts/yr/kg, and no events are observed in the interval $[3.2-10]$ MeV. We therefore derive a lower limit on the half-life of $0 u\beta\beta$ decays in $^{100}$Mo of $T_{1/2}(0 u\beta\beta)> 1.1 \times 10^{24}$ yr at the $90\%$ Confidence Level, under the hypothesis of light Majorana neutrino exchange. Depending on the model used for calculating nuclear matrix elements, the limit for the effective Majorana neutrino mass lies in the range $\langle m_{ u} \rangle < 0.33$--$0.62$ eV. We also report constraints on other lepton-number violating mechanisms for $0 u\beta\beta$ decays.